This invention relates to an end fitting for a central vacuum cleaner hose. More particularly, this invention relates to a universal end fitting for a central vacuum cleaner hose that can be used in installations in which electrical power for accessories is provided through the central vacuum cleaner wall outlets, as well as installations in which electrical power for accessories must be provided separately.
A central vacuum cleaner system installed in a house (or other building) typically includes a vacuum source and dirt collection apparatus in a central location, such as the basement of the house, connected by ductwork to vacuum cleaner wall outlets located strategically throughout the house (e.g., one outlet per room). The user goes from room to room--or, more accurately, from outlet to outlet--carrying only a vacuum cleaner hose and an array of common vacuum cleaner attachments (e.g., wand sections, floor brush, dusting brush, upholstery brush), for which a special caddy may be provided. Thus, the user need not carry a heavy vacuum cleaner canister around the house.
Each vacuum cleaner outlet includes a vacuum port which communicates with the ductwork in the wall and with the fluid passage of the hose to provide suction cleaning air to the attachment at the other end of the hose. Each outlet also typically includes two contacts to low voltage (usually direct-current) control conductors for actuating the central vacuum cleaner system. The system can be set up so that corresponding contacts on the hose end fitting electrically connect together (i.e., "short") the two contacts in the wall outlet, activating the central vacuum apparatus on insertion of the end fitting into the outlet. Alternatively, the system can be set up so that the contacts on the hose end fitting are connected to conductors in the hose that in turn connect to a switch at the far end of the hose, allowing the user to activate and deactivate the system at the point of actual use, away from the outlet.
In addition to the passive vacuum cleaner attachments mentioned above, the system may include a floor and carpet cleaning attachment with a powered brush for agitating the carpet to extract more dirt, again similar to the same type of attachment used with ordinary canister vacuum cleaners. If such an attachment is provided, a way must be provided to supply electrical power to the powered attachment, which normally requires an ordinary household alternating-current supply.
One solution is to provide a separate power cord on the attachment itself which can be attached by the user directly to an ordinary household electrical outlet. However, that would require the user to manage both the hose and the separate power cord, each of which could be trailing in a different direction. In addition, manufacturers of such attachments frequently also provide such attachments for canister vacuum cleaners, and it is therefore desirable that the same attachment can be used with both types of systems. Accordingly, it is preferable for the electrical supply for the attachment to be provided through conductors in the hose, as it is with canister vacuum cleaners.
Two schemes for providing power through a central vacuum cleaner hose to an attachment are commonly used. In one scheme, the central vacuum cleaner wall outlet has a second set of contacts--usually recessed female contacts for safety reasons--connected to a supply of ordinary household power. A mating plug--usually male--in the hose end fitting engages the power contacts in the wall outlet and connects to the power conductors in the hose.
In the second scheme, the wall outlet is not provided with power contacts. For example, if the central vacuum cleaner system is being installed in an existing house, rather than as part of new construction, it may be difficult to run power lines through the walls in addition to the central vacuum cleaner duct. In the second scheme, then, the male contacts on the hose end fitting face away from the wall, and an auxiliary power cord is provided to connect at one end to the male contacts and at the other end to an ordinary household electrical outlet.
It is known to provide central vacuum cleaner hose end fittings with contacts that can be configured to connect either to power contacts in the central vacuum cleaner wall outlet or to an ordinary electrical outlet. This has the advantage that manufacturers can supply a single type of hose that can be configured at the point of sale or installation. Configuration by the user is usually not necessary, as the user will generally have either one type of vacuum system outlet or the other. It is generally sufficient that the installer configure the end fitting once.
Known "universal" hose end fittings, as these adjustable fittings are called, typically include an electrical connector body having two prongs connected to power conductors in the hose. The connector body can be detached from the hose--either by disassembling the end fitting or by releasing a screw or similar fastener--reversed in direction, and reattached (the conductors are never disconnected). This requires that the connector body be realigned, so that the prongs protrude the correct distance in the correct direction to mate with the female contacts in the outlet.
It would be desirable to be able to provide a central vacuum cleaner hose end fitting having a reversible electrical connector body that can be reversed without being disconnected from the end fitting, and which accordingly need not be realigned after being reversed.